Pakistan's local media say the country's top court has ordered the anti-graft agency to release former Prime Minister Imran Khan.

His recent arrest triggered outbreaks of violence across the country.

Khan was arrested in a land fraud case on Tuesday, and was reportedly charged in a separate case the day after. Local media say he allegedly sold state gifts during his four years in power.

Some demonstrations have escalated, with protestors destroying police vehicles and setting fire to a radio station. At least 4 people were killed and over 80 others wounded in the northwestern city of Peshawar on Wednesday as crowds clashed with security forces.

Authorities in the capital Islamabad and some provinces have reportedly called in the military to restore order.